Sulfosuccinic acid polyesters of fatty acid monoglycerides



Patented May 5, 1953 SULFOSUCCINIC ACID POLYES-TERS OF FATTY ACID MONOGLYCERIDES Jack '1. Thurston, Riverside, Conn., assignor to American Cyanamid Company, New York, N. Y., a corporation of Maine No Drawing. Application October 4, 1950, Serial No. 188,485

11 Claims. (01. 1l7-139.5)

This invention relates to a new class of compounds which have outstanding characteristics as non-yellowing softening agents for cotton and rayon textiles during hot finishing treatments and storage thereof. More particularly, the invention relates to a class of sulfosuccinic acid polyesters of fatty acid monoglycerides possessing these desirable characteristics. The invention includes the novel softening agents, the method of softening textiles therewith, and the thereby improved textile products.

In the course of their manufacture and finishing, cotton and rayon textiles are usually sub- J'ected to heat treatments. Often the textiles are treated with fillers such as starch, gum tragacanth, gum ghatti, dextrines, and the like, in order to impart body to the cloth. These treatments result in the production of relatively stiff fabric which is harsh feeling and less desirable commercially than fabrics having a soft hand.

tiles, for imparting thereto increased lubricity. Among the compounds employed by the art were sulfonated hydrocarbons, waxes, stearates, and sulfated oils such as cottonseed oil, peanut oil, and similar sulfated oil products. In view of the economics involved in textile manufacture, some of the most widely employed softening agents have been sulfated and/or sulfonated tallow, and sulfated and/or sulfonatecl monoand diglycerides of tallow, cottonseed oil, coconut oil and others of the relatively long carbon chain fatty acids. However, the incorporation of even small amounts of these agents in cotton and rayon textiles has resulted in yellowing of the fabric subsequent to the finishing thereof. This is primarily due to the fact that washed and/or sized fabric is ordinarily dried at temperatures of about 250-460 F. and is then immediately rolled into bolts. The inner layers of the bolted cloth retain the heat for a period of several days during which time these sulfated or sulfonated softening agents, all of which are relatively sensitive to heat, deteriorate sufficiently to cause serious yellowing of the treated fabric. Similarly, in the fabrication of garments from the treated textile materials, the cloth is frequently subjected to hot pressing operations which cause these softening agents to deteriorate. Therefore, although sulfated and sulfonated fatty acids and fatty acid glycerides are recognised as outstanding textile softening agents, their lack of heat stability has rendered them unfit for many textile finishing operations.

It has now been discovered, quite unexpectedly,

that the members of a new class of polyesters of sulfosuccinic acid with substantially equimolecular quantities of monoglycerides of fatty acids having 12 to 18 carbon atoms possess outstanding textile softening properties without any appreci able tendency to deteriorate under the influence of heat. In addition to these desirable qualities, this class of compounds has also been found to plasticize the starch sizes employed by the textile industry. Thus, the novel class of compounds of this invention provides the textile industry with a dual purpose agent which acts both as a nonyellowing textile softeningcompound and a plasticizer for starch-sized fabrics.

A further important advantage of the invention resides in the fact that all of the starting materials of the polyesters of sulfosuccinic acid are readily available commercially at relatively low cost and, as pointed out above, this feature is extremely attractive to the manufacturers of textiles.

The novel class of non-yellowing textile softening agents of the invention have the general formula in which R; is an aliphatic radical containing from 11 to 17 carbon atoms Me is a salt-forming cation, and n is a number from 2-10.

R, which represents the residue of a fatty acid having from 12 to 18 carbon atoms, may be obtained from such raw materials as, for example, lauric, myristic, palmitic and stearic acids as well as the commercially available mixtures of fatty acids obtained from tallow, coconut acids, cottonseed acids, and the like compositions. The succinic radical is obtained from inaleic acid or its equivalent such as maleic anhydride and fumaric acid.

Briefly, the polyesters are prepared by condensing substanially equimolecular proportions of the desired fatty acid monoglyceride, or mixtures of fatty acid monoglyceride and diglyceride, with maleic acid or its equivalent. The condensation reaction is continued until the desired number of of ester units have united. Me in the above formula is then obtained by substantially complete sulfonation of the polymeric compound with a bisulfite or metabisulfite containing a cationic salt-forming substituent such as any of the alkali metals or ammonium. Preferably, the sulfonation is carried out by heating the polyester with erating procedure.

an aqueous solution of alkali metal or ammonium bisulfite or metabisulfite to obtain directly the corresponding salt.

Salts of other bases may be readily obtained by first acidifying an alcoholic solution of the alkali metal or ammom'um-- salts whereby the free polyester of sulfosuccinic acid is obtained, filtering off the inorganic salt of the acid used and reacting the acid with the desired base.

Although they are not ordinarily vemployedin.

textile finishing treatments, salts of the polyvalent metals such as calcium, barium, zinc, lead, cadmium, and the like may be prepared :if de:- sired by adding stoichiometric quantities-of their oxides or hydroxides to the alcoholic polymeric sulfosuccinic acid ester solution followed by stirring until the salt formation is complete. Salts of organic bases such as methyl, ethyl, or

butyl amine, guanylurea, guanidine, hydroxyethylguanidine, biguanide, ethanolamine, triethanolamine, or higher aliphatic amines, aromaticamines, and heterocyclic 'bases .such as nicotine, pyridine, quinoline, and alkaloids may also be prepared by the same. method. as wells-as by direct sulfonation employing the sulfites. and

bisulfites of theorganic bases.

ulngeneral, thepolyesters of sulfosuccinic acid .of the invention range from viscous liquids to hard waxy. compositions depending on the number of. ester units present and, to; some extent,

.on"the particular fatty acids employed, It has .been found that polymers containing from 2 to about: 10. ester unitapossess the most desirable textile softening characteristics andall of. these products are dispersible inziwateriand some of them are also solub1e.in hydrocarbonsolvents. Onthe other hand, the corresponding monomeric sulfosuccinates. are. i unsatisfactory. 'as-.textile softeners due to their: heat instability, .while the corresponding polyesters containingiin excess .of

an average of 10 ester units are insufficiently dispersible or soluble to permit their use in textile treatments. convenientmethod of following the course of the polymerization'reaction "resides in the determination of the acid number of the polyester as expressed in ml. of KOH required to exactly"neutralize 1 g. of product. The acid number decreases as' "the polymerization progresses. For example, an acid-number of about =40-will 'indica'tethat"the -product "contaihs an 1..

if the textile isto be sized' at the same time, in

an' aqueous size bath. The textile material is thereafter impregnated in the bath to a "wet pickup of substantially 100% of'the weight of fabric and then dried according to' normal ophand iii the product'. Onthe other hand, where a sizing agent is used, it is sometimes necessary to increase the softening agent content to about or more to obtain the desired improvement in softness of hand in the treated fabric.

" 'The invention willbe more fully described by It should be the following specific examples:

Ordinarily, where no sizing 4 understood, however, that although these examples may describe in detail some of the specific features of the invention, they are given primarily for purposes of illustration and the invention in its broader aspects is not limited thereto.

' 1 Example 1 A mixture of 362 g. of commercial distilled cottonseed acid monoglyceride, having an equivalent weightof about 362, with 98 g. of maleic anhydride and 5 g. of 2,2-methylene-bis-(6- tert-butyl-p-cresol) was melted and heated at 95-100 C. for minutes under an atmosphere of nitrogen, forming a clear yellow oil. The temperature was then raised to 175 C. While the temperature was held in the range of 175-186 Cfduring two hours and ten minutes, nitrogen was blown through the reaction mixture at a rate of 200-400 cc. per minute, and a total of 10.2 ml. of water formed in the esterification was collected in-a trap. On cooling the reaction mixtuije'formd'-a"-viscous yellow syrup. This mat 'ial had anacid number'of 43.0 and the average chain-length was 2.9 ester units.

This polymaleate ester, 350 g., was sulfonated in 600 "ml. of ethanoland 300 ml. of water with 34'.5g.'of sodium su'lfi'te'and 59 g. of 97% sodium 'rnetab i'sulfite. These reagents were mixed and refluxed'with vigorous agitation for a total of "78 hours. Iodometric titration of a sample of the reaction mixture for unreacted'sulfite indicated that-'the'rea'ction was about complete. The reaction mixture-was concentrated by evaporation on the'steam' bathto a thick, viscous syrup. The material was soluble in water and formed a faintly opalescentfoaming solution 7 .-:,Example. .2

'I','.(A')' .A mixture of" 2158 "gQbf commercial hydrogenated tallow,'470'g..of 98% glycerol and 2.5 g. of. calciumlhyd'roxidejwas'placed'in 'aj'5 liter B-necked flask equipped with stirrer, thermomete'r, gas inlet tube and air condenser. The mixture'was heatedto220-230" C. for 90 minutes .under'an atmosphere of nitrogen. It was then cooledQto .C. and: filtered using a steamheatedlBuchner funnel. I

The product was a light yellow clear oilv which solidified to a 'waxy whitesolid'oncooling. .[Kmixture 'of 353 .g. of this hydrogenated tallow 'a'cid 'monoglyceride, 98. g. of maleic anhydri'de, and 3 50 ml.'of"xylene washeated to r'e'fiux'in a nitrogen atmosphere, removing the water formed inthe esterificati'onjwith a trap. After 1 /2 hours at a maximum temperature of 143'C., "there was collected 3.5fml. of water. The reaction was then stopped and the xylene stripped Torr under, vacuum, up to a temperature of 147? C. The crude ester was filtered while hot to remove a small amount of insoluble resin. There was obtained 405 g. of product, having an acid number of 79.2 and an average chain length of 1.6 es e un s.

A, mixture of 400 g. of this maleate, 72 g. of sodium sulfite, and 33 g. of sodium metabisulfite in, 600 ml. of ethanol and 300 ml. of water was heated to reflux for 12hours. Titration of a sample indicated that the reaction was 86% complete The reaction mixture was treated with a small amount of hydrogen peroxide to oxidize the unreacted sulfite and bisulfite, filtered, and evaporated on a steam bath. The product was alight, cream-colored hard wax.

'(Bl ln a second preparation, the same quantities 'oFm'aterialsWere heated to reflux with stirinorganic salts.

l 4 1 g. of sodium sulfite, g. of sodium metabisulfite, 500 m1. of ethanol, and 275 ml. of water was refluxed with vigorous agitation for hours. At the end or" this time, titration indicated that the sulfonation reaction was complete. The mixture was treated with sufficient 30% hydrogen peroxide to oxidize the excess sodium bisulfite, and then filtered to remove the precipitated The filtrate was evaporated on a steam bath. After drying, a tan Wax product was obtained.

(C) In a third preparation, the same quantities of hydrogenated tallow acid monoglyceride, maleic anhydride and xylene were used as above.

The mixture was heated to reflux in a hydrogen atmosphereat 149 C. During 3% hours, the temperature of reflux was raised to 180 C. by the gradual withdrawal of 280 ml. of xylene, together with 14 ml. or" water formed in the esterification. The reaction mixture was then stripped of xylene under vacuum. After filtering to remove insoluble resin the polyester was poured into a tray. It did not solidify, but remained as a bright yellow, extremely viscous liquid. The yield was 352 g. of product, having an acid number of 18.5 and an average chain length of 7.0 ester units.

A mixture of 34-8 3'. of this polymaleate, 15 g. of sodium sulfite, 73 g. of sodium metabisuliite, 525 ml. of ethanol, and 266 ml. of water was heated to reflux with stirring for 60 hours. The reaction was then about 75% complete. The

reaction mixture was thereafter treated with hydrogen peroxide and filtered. The filtrate was neutralized to p11 7 with 40% sodium hydroxide solution. This solution was then evaporated on a steam bath and the product dried. There was obtained a viscous yellow syrup which was readily dispersible in water.

Ewample 3 A mixture of 328 g. (0.5 incl) of coconut oil, 92 g. (1.0 mol) of 98% glycerol, and 0.3 g. calcium hydroxide was-heated to 220 C. over 21. i5 minute period in an atmosphere of carbon dioxide, and maintained at 220-228 C. for an additional 15 minutes. During this time, the volume of methanol required to a turbid solution with a 1 ml. sample of the reaction mixture rose from a few drops to more than 100 ml., indicating complete conversion of the triglyceride to coconut acid monoglyceride. The reaction mixture was cooled to 75 (3., stirred with a filter aid and filtered hot. The yield of clear yellow oil product was 393 -g., 96% of theory.

A mixture or" 1'73 g. of the above coconut oil monoglyceride, 53 g. of maleic anhydride, and 50 ml. of xylene was heated to reflux with stirring, removing the water formed in a trap. After one hour at 170-i86 (3., 81% of the theoretical amount of water had been removed and some resin had formed. The xylene was then distilled under water pump pressure leaving the polyester as a viscous yellow oil weighing 213 g. The acid number was 34, indicating an ester chain. length of 4.5 units.

208 g. of this maleate polyester was mixed with 63 g. of 97% sodium metabisulfite, 250 ml. of ethanol and ml. of water, and the mixture refluxed for 6 hours. The reaction mixture separated into two liquid layers on cooling and was diluted with 250 ml. of ethanol. The product was only slightly soluble in ethanol and the aqueous layer which formed solid paste was separated by decantation'from the alcohol. Upon evaporation of the paste on a steam bath, 228 g. of a brittle, light yellow glassy wax was obtained.

The procedure of the above example was re peated except that in the sulfonation of the maleate polyester ethanolamine bisulflte was employed in place of the sodium metabisulfite. The product obtained was a water dispersible light yellow wax.

Example 4 152 g. of stea-royl chloride, which was prepared by reaction of stearic acid with phosphorus trichloride, was added to a solution of 16 g. of dry glycerol in ml. of dry pyridine. The resulting solution was heated on steam bath for 80 minutes and then poured onto crushed ice. The crude ester was extracted with hot butanol and the solution which formed was washed with hydrochloric acid until the pyridine was removed, after which it was washed twice with water. The butanol solution was thereafter evaporated on a steam bath and, subsequent to drying in a vacuum desiccator, 200 g. oi a light cream colored wax product was obtained.

A mixture of 65 g. of the above described glyceryl monostearate, 18 g. of maleic anhydride, and 100 ml. of toluene was heated for one hour at 105 C. and the toluene was then removed under vacuum. The resulting 35 g. of cream colored waxy polyester had an acid number of 71.6, indicating an average chain length oi 1.3 ester units. The product was mixed with lei g. of sodium suliite, 8 g. of sodium inetabisulfite, 190 m1. of ethanol, and 50 m1. of water. The sodium sulfite was employed to neutralize the acidity of the polyester. The mixture was refluxed with stirring for 24 hours and the product, which precipitated on cooling, was filtered. It was a firm white paste containing 62% solids.

In a second preparation of glyceryl monostearate polyester, 65 g. of glyceryl monostearate, and 18 g. of maleic anhydrlde in 75 ml. of xylene was refluxed. Water and xylene were removed until the temperature rose to C. After 4 hours the crude ester had an acid number 01 52.5 and an average chain length of 2.3 ester units. This maleate polyester was sulfonated with an excess of guanidine sulfite to obtain a tan paste product.

In a third preparation the same quantities of glyceryl monostearate and maleic anhydride were employed. The mixture was refluxed over a period of 5 hours during which time 10 ml. of the xylene were removed. Upon cooling, filtering, and removal or the xylene s "ipping, the polyester product had an acid number of 17.6 and an average chain length of 7.5 ester units. This product was su'ifonated with an excess of guanylurea suliite and resulted in a cream colored paste which was easily dispersed in water.

Example 5 Lauroyl chloride was prepared by the reaction preparation data.

slof; lauric i old .and; phosphorus: triehloride, after which the product was freed of hydrogen chloi'ride, by "passing carbon dioxide vtherethrough. 1 137 .g. (0.5 mol) of the product was added to a solution of 46 g. (0.5 mol) of dry glycerol in "160 ml. of dry pyridine. The solution was heated :-on a steam bath for 30 minutes and then poured ionto. crushed ice. Upon extraction of thecrude sestenwith hot butanol and water washing followed :by;; drying, there was obtained a light tan- I -n ish colored wax product.

49.3 g. (0.18 mol) of the above described glyceryl monolaurate was mixed with 18 g. (0.18 mol) of maleic anhydride and 100 ml. of xylene. The

mixture was refluxed with removal of Water ;and,xylene until the temperature rose to 170 *("h' After 4 hours the polyester acid number indicated- -an average chain length of 2;?- ester -units. Thereafter, the polyester was mixed with 14 g. of sodium sulfite, 8 g. of sodium metabisulfite, 100 ml. of ethanol, and 50 ml. of water. The mixture was refluxed with stirring for 24 hours and the resulting paste was dissolved in ethanol after which the solution was acidified with sulfuric acid to obtain the free polyester. The barium salt was then prepared by the addition of barium oxide with stirring until substantial neutrality was reached. The product was a Water dispersible tan Wax.

Example 6 The procedure of Example was repeated employing equivalent amounts of myristic acid instead of lauric acid. Following the preparation of the polyester by the condensation of glyceryl monomyristate and maleic anhydride, the product was sulfonated with sodium metabisulfite, after which the free polyester acid was produced. The pyridine salt was thereafter prepared to obtain a yellowish paste which was easily dispersible in water.

Example 7 A series of sodium polysulfosuccinates of tallow mono glycerides was prepared in a manner similar to that of Example 2. The esterification with maleic anhydride was carried out over varying periods of time to obtain ester units of from 2.03 to 6.15. The table below gives the In all instances there were used 3.06 mols of the tallow monoglyceride and 3.0 mols of maleic anhydride, while the esterification was carried out at 175 C. The reaction time includes the period of heating from room temperature to 175 C.

- Sulfona- Reaction Acid Chain Percent Yleld tion N 0. me, No. 01 Length of Sulfonahrs Ester Ester Percent tion g iY by i s Reflectance Decrease I ppearance of Solubility of Sulfosuc-.

' Sulfosuccinate i r-, liqlygter 'dispcrsible at 30. 0.. 0'0

dispersible at 60 0" light tan past dispersible at 60 C white paste, dispersible at 75 G i light tan paste): dispersible at boilingtemperature.

Example 8 The procedure of Example 3 was repeated employing 5 mols of tallow monoglyceride and one mol of maleic anhydride. Esterification was effected at a temperature of 140-179-C-. over a period of 8.3 hours resulting in a maleic polyester having a chain length of 9.35 ester units. .Thepolyester was sulfonated over a period of 43 hours and the product was a light tan paste. Upon evaluation the product was superior to a commercially available softening agent both in the hand of the treated textile and in the ability of the product to prevent gelation of a 1% starch bath. The light reflectance, evaluated as in Example 4, was +2.8.

Iclaim:

l. A polyester of sulfosuccinic acid with a substantially equimolecular quantity of a monoglyceride of a fatty acid having 12-18 carbon atoms, said polyester having at least 2 ester units.

2. A polyester of sulfosuccinic acid with a substantially equimolecular quantity of a monoglyceride of a mixture of fatty acids having 12-18 carbon atoms, said polyester having at least 2 ester units.

3. A polyester of sulfosuccinic acid with a substantially equimolecular quantity of cottonseed acid monoglyercide, said polyester having at least 2 ester units.

4. A polyester of sulfosuccinic acid with a substantially equimolecular quantity of hydrogenated tallow acid monoglyceride, said polyester having at least 2 ester units.

5. A polyester of sulfosuccinic acid with a substantially equimolecular quantity of coconut acid monoglyceride, said polyester having at least 2 ester units.

6. A polyester of sulfosuccinic acid with a substantially equimolecular quantity of glyceryl monostearate, said polyester having at least 2 ester units.

'7. A method of preparing a non-yellowing sulfosuccinic acid polyester of a fatty acid monoglyceride, which consists essentially in esterifying a mixture of substantially equimolecular quantities of monoglyceride of one or more fatty acids of 12-18 carton atoms and a member of the group consisting of maleic and fumaric acids by heating said mixture until an acid number between about 40 and about 10 is obtained and thereafter sulfonating the product by reaction thereof with a water soluble bisulfite.

8. Amethod of softening textile materials which comprises impregnating the textile with an aqueous dispersion of a polyester of sulfosuccinic acid with a substantially equimolecular quantity of a monoglyceride of a fatty acid having 12-18 carbon atoms, said polyester having at least 2 ester 9 units, and thereafter drying the impregnated textile material.

9. A method as in claim 8, in which the aqueous dispersion contains from 0.5% to about 3% by weight of the polyester softening agent.

10. A method as in claim 9, in which the uptake of aqueous dispersion by the textile material is substantially 100% of the weight of the fabric.

11. A textile material characterized by improved softness of hand consisting essentially of a textile fabric having distributed uniformly therethrough from about 0.5% to about 3% by weight of a polyester of sulfosuccinic acid with a substantially equimolecular quantity of a monoglyeride of a fatty acid having 12-18 carbon atoms,

said polyester having at least 2 ester units.

JACK T. THURSTON.

References Cited in the file of this patent UNITED STATES PATENTS 

8. A METHOD OF SOFTENING TEXTILE MATERIALS WHICH COMPRISES IMPREGNATING THE TEXTILE WITH AN AQUEOUS DISPERSION OF A POLYESTER OF SULFOSUCCINIC ACID WITH A SUBSTANTIALLY EQUIMOLECULAR QUANTITY OF A MONOGLYCERIDE OF A FATTY ACID HAVING 12-18 CARBON ATOMS, SAID POLYESTER HAVING AT LEAST 2 ESTER UNITS, AND THEREAFTER DRYING THE IMPREGNATED TEXTILE MATERIAL. 